&#34;Air cooling and purification apparatus intended for a cryogenic air distillation unit&#34;

ABSTRACT

An apparatus for cooling and purifying a stream of air comprises a building, a cooling tower, for cooling by direct contact with water, two purification bottles, each of vertical axis, a pipe for sending water to the cooling tower, a pipe for sending air to the cooling tower, a pipe for sending cooled air from the tower to the purification bottles and a system of valves and piping for connecting the two bottles to the cooling tower, this assembly being located inside the building, and the two bottles and the tower being outside the building, the two bottles and the assembly being placed on either side of a wall of the building, the bottles being placed along the wall and the tower being positioned between the two bottles.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a §371 of International PCT Application PCT/EP2011/060417, filed Jun. 22, 2011, which claims the benefit of FR1055603, filed Jul. 9, 2010, both of which are herein incorporated by reference in their entireties.

TECHNICAL FIELD OF THE INVENTION

The present invention relates to an air cooling and purification apparatus intended for a cryogenic air distillation unit.

BACKGROUND

In an apparatus that separates air by cryogenic distillation, the air is compressed in a compressor and then cooled by direct exchange of heat with air in a cooling tower. The cooled air is then purified. The purification processes in the air separation units chiefly remove water and CO₂ from the air before it enters the cryogenic distillation unit positioned in a cold box. A set of valves and pipework allow carriage of the air that is to be purified and of the impure nitrogen used for regenerating the purification cylinders. This set of valves and piping is laid “flat” on the ground where it occupies a great deal of space. The ratio of the height to the length of the set is close to 1.

When installing this set of valves and piping inside a new building (for reasons of excessive cold or heat or for any other reason) it is advantageous to reduce the width of this set in order to reduce the width of the building that has to be erected. Likewise, to install this set on an existing building (which tends to be somewhat long and not very wide), reducing the width of this set of pipework and valves can be of considerable help.

One of the ways of reducing the width of this set is, through a different design of pipework, to lengthen this set. The ratio between the height and the width of the set then becomes very much smaller than 1.

As a result, the inter-axis distance of these purification cylinders connected to this set will also lengthen.

An apparatus according to the preamble of claim 1 is described in EP-A-1672301.

SUMMARY OF THE INVENTION

According to the invention, the air cooling tower that cools by direct contact with the water is installed between the two purification cylinders.

One subject of the invention provides an apparatus for cooling and purifying a stream of air, comprising a cooling tower that cools by direct contact with water, two purification cylinders, each of vertical axis, a pipe for conveying water to the cooling tower, a pipe for conveying air to the cooling tower, the tower being located between the two cylinders, a pipe for conveying cooled air from the tower to the purification cylinders and a set of valves and piping connecting the two cylinders to the cooling tower, characterized in that the apparatus comprises a building, the set being situated inside the building and the two cylinders and the tower being outside the building, the two cylinders and the set being positioned on either side of a wall of the building, with the cylinders positioned along the wall.

According to other optional features of the apparatus:

-   -   the center of the tower viewed from above is situated on the         mid-line between the centers of the two cylinders, viewed from         above;     -   the centers of the two cylinders and of the tower when viewed         from above form a straight line;     -   the centers of the two cylinders and of the tower when viewed         from above form an obtuse-angled triangle;     -   the building also contains at least one compressor and/or at         least one turbine and/or at least one distillation column;     -   the ratio between the dimension of the set in the vertical         direction and the dimension in the horizontal direction is less         than 1;     -   the wall constitutes the longest wall of the building, the         building being of rectangular section.     -   the ratio between the length of the wall and the width of the         building is greater than 2.

Another subject of the invention provides an air separation apparatus comprising a cooling and purifying apparatus as described hereinabove.

The air separation apparatus may comprise a compressor inside the building which is an air compressor connected to the cooling tower and/or a turbine, inside the building, which is an air turbine connected to the purification cylinders and/or a distillation column inside the building and connected to the purification cylinders.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features, aspects, and advantages of the present invention will become better understood with regard to the following description, claims, and accompanying drawings. It is to be noted, however, that the drawings illustrate only several embodiments of the invention and are therefore not to be considered limiting of the invention's scope as it can admit to other equally effective embodiments.

FIG. 1 represents an apparatus in accordance with an embodiment of the invention.

DETAILED DESCRIPTION

The invention will be described in greater detail with reference to the figure. FIG. 1 illustrates an apparatus according to an embodiment of the invention.

The apparatus comprises a cooling tower 1 that cools by direct contact with water, two purification cylinders 3A, 3B for purifying the air with respect to water and with respect to CO₂ and a building 5 containing at least one set 7 of piping and valves to allow the air from the tower 1 to be conveyed to the cylinders 3A, 3B. Some of the piping of the set 7 passes through the wall 9 of the building 5. The wall 9 is the longest wall of the building 5 which is of rectangular section. The ratio between the length of the wall 9 and the width of the building is preferably greater than 2.

The ratio between the dimension of the set 7 in the vertical direction and the dimension in the horizontal direction is less than 1.

The two cylinders 3A, 3B and the tower are arranged along the wall 9 in such a way that their centres, viewed from above, form a straight line parallel to the wall. The tower is positioned on the mid-line between the two cylinders.

The tower 1 can be slightly closer to or further away from the wall 9 than the two cylinders 3A, 3B, so that the centres of the tower and of the two cylinders form an obtuse-angled triangle.

The building 5 may also contain a compressor and/or a turbine and/or a distillation column of the air separation apparatus of which the cooling and purification apparatus forms part.

The air separation apparatus may comprise a compressor inside the building 5 which is an air compressor connected to the cooling tower 1 and/or a turbine, inside the building 5, which is an air turbine connected to the purification cylinders 3A, 3B and/or a distillation column inside the building 5 and connected to the purification cylinders 3A, 3B. 

1-14. (canceled)
 15. An apparatus for cooling and purifying a stream of air comprising: a cooling tower that cools by direct contact with water; two purification cylinders, each of vertical axis; a pipe for conveying water to the cooling tower, the tower being located between the two cylinders; a pipe for conveying air to the cooling tower; a pipe for conveying cooled air from the tower to the purification cylinders; a set of valves and piping connecting the two cylinders to the cooling tower; and a building, wherein the set of valves and piping are disposed inside the building, wherein the two purification cylinders and the cooling tower are disposed outside the building, wherein the two cylinders and the set of valves and piping are positioned on either side of a wall of the building, with the purification cylinders positioned along the wall.
 16. The apparatus as claimed in claim 15, in which the center of the tower viewed from above is situated on the mid line between the centers of the two cylinders, viewed from above.
 17. The apparatus as claimed in claim 15, wherein the centers of the two cylinders and of the tower when viewed from above form a straight line.
 18. The apparatus as claimed in claim 15, wherein the centers of the two cylinders and of the tower when viewed from above form an obtuse angled triangle.
 19. The apparatus as claimed in claim 15, in which the building further comprises a device selected from the group consisting of a compressor, a turbine, a distillation column, and combinations thereof
 20. The apparatus as claimed in claim 15, in which the ratio between the dimension of the set of valves and piping in the vertical direction and the dimension in the horizontal direction is less than
 1. 21. The apparatus as claimed in claim 15, in which the wall constitutes the longest wall of the building, the building being of rectangular section.
 22. The apparatus as claimed in claim 21, in which the ratio between the length of the wall and the width of the building is greater than
 2. 23. The apparatus as claimed in claim 15, in which the tower is closer to the wall than the two cylinders.
 24. The apparatus as claimed in claim 15, in which the tower is further away from the wall than the two cylinders.
 25. The apparatus as claimed in claim 15, wherein the apparatus is used to provide cooling and purification of air for an air separation apparatus.
 26. The apparatus as claimed in claim 19, wherein the apparatus is used to provide cooling and purification of air for an air separation apparatus, wherein the compressor is an air compressor connected to the cooling tower.
 27. The apparatus as claimed in claim 19, wherein the apparatus is used to provide cooling and purification of air for an air separation apparatus, wherein the turbine is an air turbine connected to the purification cylinders.
 28. The apparatus as claimed in claim 19, wherein the apparatus is used to provide cooling and purification of air for an air separation apparatus, wherein the distillation column is an air distillation column connected to the purification cylinders. 